Internal-combustion engine conditioning compounds



Patented June 28, 1949 INTERNAL COMBUSTION ENGINE I CONDITIONINGCOMPOUNDS Raymond'IuPotter, Lorain, and' Harry Gillett, Hudson, Ohio,assignors to The-Standard Oil Company, Cleveland, Ohio, acorporation of=1 Ohio No Drawing. Application "September 25, 1946, Serial No. 699,350

Internal combustion engines are commonly flushed out and cleaned with apetroleum distillate before being replenished with freshlubricating-nil. This mechanically-washes the old oil oif of the metalsurtaoesand slushes out loose surfaces not subject to mnechanicalrubbing.

Such oxygen-containing compondsare insoluble inr hy'drooarbon typesolvents, and from this standpointit can be real-ized that no amount ofwashing with hydrocarbon distillates can accomplish cleaning. We-havenow found, however,..that.-a composition as set forth hereinafter isable to exert a substantial dissolving and cleaning action on suchcoated-ondepositsin engines, including conditions involvingring-sticking, etc.

Other objects and advantages of the invention will betapparent from thefollowing. description.

:To theaccomplishmentof'the foregoing and related ends, .the..invention, then, comprises the features hereinafter fully described, andparticularlyapeinted out 'in' the claims, theiollowing descriptionsetting forth in detail certainxillustrative embodiments of theinvention, these'being indicative however, of but a few of the variousways in which the principle of the invention may be employed.

To make up our compound, we employ an ether and a hydrocarbon incompatible combination'. For this, the ether is sufficiently highboiling to not be fugitive under the conditions in which the compoundmust be used, i. e. in an engine which generally has not cooled downfrom its operating state. This ether is a glycol monoether, and may beof the group of glycolmonomethyl ether, glycolmonoethyl ether,glycolmonobutyl ether, glycolmonobenzyl ether, and beta hydroxyethylphenyl ether, and all these are hereinafter referred to concisely asglycol mono-ethers. Ordinarily we prefer the glycolmonobutyl ether. Thisand the glycolmonoethyl -61.Claims. (014252-4170) ether are in generalparticularly desirable; that is, aglycolmono-alkyl ether in which thealkyl has at least two carbon atoms and not more than four. And, Withthe glycol ether we mix a hydrocarbon distillate.

The relative proportions of the glycol ether and the hydrocarbondistillate may vary somewhat, depending upon particular conditions to beencountered, and while in many cases equal parts are desirable-in otherinstances we may apply a smaller proportion of the ether from 50% downto about 10%. This is a practical range of proportions -for=goodresults, and variations therefrom are generally not desirable, asamounts down-to -one per cent for instance are less eifective, andamounts materially about fifty per cent may be=of==undesirably low flashpoint especially if one of the lighter glycol compounds beused.

:These particular components are, as aforeindicated, highlycompatiblewith each other to a homogeneous stable composition, and thepreparation of the material requires merely an adequate mixing togetherof a stated proportion of the ingredients.

In use, while a fouled engine for instance which is to be treated-maybedrained of the old oil, and a charge of our treating compound beintroduced into the-crank case, it is not however necessary -to drainthe crank case prior to flushing. 'Thus the flushing solution may beadded directly-to theold oil in the crank case. It is beneficial to'addaquantity of liquid in the crank case during the flushing operationgreater than the amount of-oil normally present. The quantity of liquidfor therlus-hing operation may desirably be about twice that of thenormal operating volume-of lubricating oil. For instance, with anordinary five-quart crank case, about five quarts of flushing solutionmay be added to the oil already present, making a total of ten quarts ofliquid for the flushing operation. Or, if the crank case be drainedfirst, preferably more than five, and up to ten or more quarts offlushing solution may be put in for the treating operation. The upperlimit or quantity of flushing mixture is set only by the ultimatecapacity of the crank case. In general, the amount of total solution maybe 2 to 2.5 times the normal crankcase capacity. The flushing solutionhaving been supplied to the engine, the engine is then operated at afast idling speed for a suflicient length of time to raise thetemperature of the flushing solution to at least R, or up to aroundabout F., the solution thus being thoroughly 3 flushed over metalsurfaces and through the recesses and passage-ways of the moving parts,after which the engine is stopped, the crank case is drained, and may bere-filled with fresh oil.

We have found that it is desirable for optimum cleansing action to keepthe Viscosity of the entire mixture in the crank case during thetreating operation below about 250 SUS at 100 -F Thus, if the crank caseis drained of old oil prior to the flushing operation, the viscosity ofthe flushing solution should not exceed 250 SUS at 100 F. Where howeverthe flushing solution is added directly to the old oil in the crankcase, the viscosity of the solution so added should be such that thetotal mixture in the crank case will fall within the desired viscosityrange. The lower ranges of viscosity for the hydrocarbon distillate willbe dictated by the boiling range of the stock, which should besufficiently high to avoid undue loss through evaporation during theflushing operation. Accordingly, the mineral oil distillate may be takenfrom a range of kerosene up through the lubricating stocks, provided theafore-stated conditions be complied with.

As an example:

About five quarts of a mixture of ten per cent glycolmonobutyl ether inabsorbent oil (a fraction just above kerosene, boiling between about 450and 750 F., having an API gravity of 30-35 and viscosity of 50 SUS at100 F.) is added to the old oil in the crank case, and the engine isidled rapidly for about 30 minutes, then is stopped, and the crank caseis drained, ready for a charge of new oil.

As illustrating the action of our compounds, the following laboratorytests may be noted. With a test apparatus including a reservoir heatedat a temperature of 170-180 R, and a container thereabove holding testpieces of sludge or varnish coated metal which are flooded with thesolution pumped from the heated reservoir, so that the solution flowsover the coated metal sample, with coated metal pieces flooded thus forthirty minutes with a hot mixture of equal parts of absorbent oil and300 red oil lubricating stock, as a control, no sludge or varnish wasremoved from the coated test plate, but when similarly a mixture offifty per cent 300 red oil and forty per cent absorbent oil and ten percent glycolmonobutyl ether, washeated and pumped over a like coated testplate for 30 minutes, a very large percentage of the sludge coating wasdissolved off and removed from the test plate. To attack varnish-likesludge coatings thus, the solvent character of the material is animportant criterion as regards its efiectiveness.

Other modes of applying the principle of the invention may be employed,change being made 4 as regards the details described, provided thefeatures stated in any of the following claims or the equivalent of suchbe employed.

We therefore particularly point out and distinctly claim as ourinvention:

1. An internal combustion engine conditioning compound, consisting ofglycolmonobutyl ether 10-50 per cent, and absorbent oil boiling betweenabout 450 and 750 F. and having an A. P. I. gravity of 30-35 andviscosity about SUS at F.

2. An internal combustion engine conditioning compound, consisting ofglycolmonobutyl ether 10-50 per cent and a hydrocarbon distillatesubstantially unvolatilized at crank case temperature.

3. An internal combustion engine conditioning compound, consisting of aglycolmonoethyl-ether 10-50 per cent, and absorbent oil boiling betweenabout 450 and 750 F. and having an A. P. I. gravity of 30-35 andviscosity about 50 SUS at 100 F. i

4. An internal combustion engine conditioning compound, consisting of aglycolmonobenzylether 10-50 per cent, and a hydrocarbon distillatesubstantially unvolatilized at crank case temperature.

5. An internal combustion engine conditioning compound, consisting of10-50 per cent of a glycolmonoalkyl ether in a hydrocarbon distillatesubstantially unvolatilized at crank case temperature, the alkyl groupof such ether having at least two carbon atoms and not over four,

6. An internal combustion engine conditioning compound, consisting of10-50 per cent of a glycolmono-ether of the class consisting ofglycolmonomethyl ether, glycolmonoethyl ether, glycolmonobutyl ether,glycolmonobenzyl ether and beta hydroxyethyl phenyl ether in ahydrocarbon distillate substantially unvolatilized at crank casetemperature,

RAYMOND I. POTTER. HARRY GIILE'I'I.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES Synthetic Organic Chemicals,pages 37 and 38, Carbide and Carbon Chemicals Corp, July 1, 1945.

